Spatial distribution on the sky of the cluster galaxies, showing the four groups recovered by the weighted gap analysis. Solid/blue circles, open circles, open squares, and dots indicate the galaxies of GV1, GV2, GV3, and GV4, respectively. The BCGN(NW) is taken as the cluster center. Very large open green squares indicate the positions of BCGN(NW) and BCGN(SE). Large/red crosses indicate ELGs.